Highway crossing signal system



4 11 FIGhI. Q

Jan. 9, 1945. w. c. ALEXANDER 2,366,690

HIGHWAY CROSSING SIGNAL SYSTEM Filed June 20, 1941 65 lbgENTOg fl ATTORNEY Paten ted'J an 9, 19415 HIGHWAY caossmc SIGNAL SYSTEM Walter 0. Alexander, Qswego, N. Y., assignor to General Railway Signal Company, Rochester,

Application June 20, 1941 Serial No. 398,940

Claims. (01. 246- 13 The present invention relates in general to highway crossing signalling systems such as used where highways cross railways, and has more particular reference to a system of this type which is of particular advantage under certain I wayside conditions.

Where a highway crosses a railway closely adjacent to a railway siding leading from the railway, there may be insufficient distancebetween the highway and the siding to give sufficient time of warning to highwaytrafiic ofan approaching train it thewarning signal isnot initiated aheadofthe siding. 'Insuchcases, the

effect of a train, approaching and crossing the.

highway, and that of a train approaching merely to the siding and then engaging in switching op- I erations, is the same with regard td the signal being initiated and continued. While the signal is discontinued when the crossing train. clears the crossing, the switching train would ordinarily.

continue thefsignal for so long as the "switching operations continue. This is very,undesirable since it teaches highway traflic to disregard such signals becauseman'y times they. indicate no danger whatsoevergand thus lays the way open to grave dangers.

In accordance with the present invention, a

means is provided for initiating thesignal upon the approach of a train, and for continuing it until the train clears the highway'if the train passes through. However, if the train engages in switching operations, or remains unduly long adjacent the siding, the signal which has been initiated is discontinued after a short period of time, whereby to avoid educating thepublic to ignore such warning crossing signals.

Further objects, purposes and characteristic ,features of the present invention will appearas the description progresses, reference being made to the accompanying drawing showing solely by; way of examplaand in no way in a limiting sense,

two forms which the invention may assume. In the drawing: j

Fig. 1 is a wholly schematic showing of one embodiment of the invention. I H I Fig. 2 is a wholly schematicshowing of a second embodiment of the invention. Referring now to the drawing, and first toFig. 1, there is here represented a stretch of single track constituted bytrack rails 3 separated into isolated sections by usual insulating joints 4 to anadjustable resistance I, while across the other I each of which in thepresent showing comprises two lamps asshown whereby if the lamps of each signal are alternately energized, and deenergized,

given which a swinging orflashing light signal is strongly arrests attention.

Across the entrance end of section I is con nected a track battery 6 connected inseries with end of this section is connecteda track relay IT.

Across the entrance end of section .2 is connected a track battery 8 in series with an adjustable resistance-9, and a contact finger ID and front point of track relay IT; whereby when relay w 1 IT is retracted section 2 is deprived of track current. Acrossthe exit end of section .2 is con nectedatrackrelay 2T.

A siding constituted by track rail II is shown as leaving the main track withinsection I whereh by an east bound train, traffic being considered,

in this embodiment, in'one direction only, "as indicated by the arrow; I2, can either proceed and pass over the highway or can remain in section I, and the adjacent partof thesiding ingoperations.

'1 For controllingthe signalsystem, there is em-.

ployed atimeelement device which includes ,a

motor Mhaving a shaft I3, carrying signal coni trol cams I4 and I5; These cams have rises,as

shown, each cam having a rise extending throughout approximately 130, with the cams positioned on the shaft so that the rises are displaced approximately $180" from each other. The cams operate on pushers I6 and I1, to movecontacts I8 and I9, between associated front and backpoints, whereby to cause the signals to swing or flash, as will appearmoreclearly below.

Motor Mthrough it shaft I3, operates a gear train 20, for operating a timinjgwheel 2I, hav

mg a rise, 22 thereon, which when rotatedto the proper position, controlsa contact 23, so as to close it on its back point. This timing wheel 2| is carried on an arm 24, pivoted at 25, and carrying an armature 26 which, when attracted by M a clutch magnet CM, moves the timing wheel into constitute sections I and 2. A highway 50,

crosses the track rails at the exit end of section 2. At each side of thetrack rails andalongside the highway is positioned a warning signal Sig.,

mesh with the gear train to therebycause the a motor shaft to turn the timing wheel. When the clutch magnet is deenergized the timing wheel is moved out of engagement with its driveand is returned to its initial position by any desired means, as, for example/a weight 21 thereon. In

the control system is involved a'stick relay IS which operates at timesito control energi zation and deenergization o f'clutch magnet CM.

Let us now assume, that a train approaches the highway and enters section .Track relay IT for switchreleases, whereby to cut trackway energy off of Sig. and the motor M are energized. The circuit for energizing the motor includes contact finger 28 and back point of relay 2T, and wires 29 and 30. The circuits for energizing the signal include one side of a source of energy, contact finger 28 and back point of relay 2T, wires 29, 3 I, 32 and 33; then in multiple through the two lamps of the right-hand signal to wire 36, and through wire 34, the lamps of the other signal and. wire 35 to wire 36, and thence through wires 31 and 38 to the other side of the source of energy. These lamps, however, are not energized in series, since each of the control contacts I8 and I9 are connected as shown to shunt out first one lamp and then the other of each signal as each contact moves from front to back point, and reverse.

The operation of the signal is similar to that which occurs when-a usual flashing relay is em- "ployed. for the control of thesignal as, for example, in the patent toO, S. Field, No. 1,969,065, granted August 7, 1934.

For example, with relay -2T down, a circuit is ,I

completed for energizing the right-hand lamp of the left-hand signal, which circuit includes contact finger, 28 and back point of relay 2T, wires 29, 31 and. 32 contactfinger I8 and front point, wires lfi and 4|, the right-hand lamp of the lefthand signal, and wires 35, 35, 31 and 38. The left-hand lampof the left-hand signal is not energized, because it is shunted out by a shunt which includes wires 32, 33, 34 and 42. In a similar manner the right-hand signal has one lamp only energized under the conditions shown. Upon contacts I8 and I3 shifting respectively to their back and front points, the previously shunted out signal lamps will be energized and the other lamps will be deenergized.

The signal does not continue to flash, however,

beyond a short period of time, unless the train proceeds into section 2, This result is due to the timer operating to cut the signal out after a short period of time, as, for example, 20 seconds. Upon the release of relay IT a circuit is completed for energizing clutch magnet CM, which circuit in.- cludes contact finger 43 and backpoint of relay IT, and contact finger '44 and back point of relay IS. This results inrneshing the timing wheel to the gear train, and after a short time contact 23 a of the timer closes to thereby energize relay IS I through a circuit which includes contact finger pletes a stick circuit for'relay IS which includes contact finger '43 and back point of relay IIT, and contact finger 44 andfro'nt point of relay IS.

Thus, if the "approaching train'remains in section- I for any length of time, and'for any reason, as, for example, for switching operations, the

signal is initiated, and is then discontinued after 7 a. short period of time with track relay IT released, track relay 2T is attracted, and stick relay IS stuck up through track relay IT released.

If, however, 'thetrain proceeds to thecrossing, the I timer. will not a have run out by the time the train enters section 2, whereby relay 2T is shunted and remains down even after the timer has completed its operation. Thus, the signal continues to be displayed although the timer is disengaged and the signal continues until the rear end of the train clears the crossing.

If the approaching train should perform switching operations, or for any other reason remain for some time in section I, and then pass through section 2 and over the highway, its speed will necessarily be so'low that adequate time of signal warning will be given.

The form just described (Fig. 1) is arranged for one-way traffic only, but the system lends itself, with modifications, to the form where a crossing can be approached from either direction on the single track, Such a system is shown in Fig. 2 wherein a stretch of single track is shown,

separated into isolated sections 3 and 4 at one.

The sources of energy and the connections thereof for some of the sections have not been shown since they are the same as in Fig. 1, and the control thereof is the same.

In this form of the invention, the two track relays 4T and ST, connected across ends ofsections 4 and 5, are interlocked, as indicated, in a usual manner, as, for example, in the patent to O; S. Field, No. 1,824,131, granted September 22, 1931. Although two-way traffic is cared for, a single timing means and motor means is employed and suitable interlock means is provided to avoid dangerous conditions and signal failures in the event of simultaneous occupancy of detector sections at the two sides of the highway.

As before, if a train approaching the highway, as, for example,,,an east bound train, enters section 3, its track relay 3T releases to cause :the release of trackrelay 4T, and energization of the signals and the operating motor MI as in the Fig. l'form of invention. l

Likewise, the clutch magnet 'CMI isenergized through a circuit which is interlocked with the sections at the other side of the highway, and which includes contact finger 54 and b ack point of relay 3T, contact finger 55-andback point of relay 48, "contact finger 5B and frontpoint of relay GT, and contact finger 51 and backpointof relay 3T. This starts the timer as before, and after it has completed'its cycle, the timer contacts 58 and 53 close on their back points, the contact finger 58 operating to close the circuit 'for energizing relay 4S through 'a circuit including contact finger 54 and back point of relay 3T, and timer contact finger 5,8 in closed position. Relay 4S then'sticksupthrou'gh contact 'fing'er 54 and back point, and its own contact finger 55 and from point.

Upon atrai'n approaching the highwayff-roman I easterly direction, as, for 'ex'amp'le, en'tering section 6, the operation is the 'sameIas described just above. Thus, for a train crossingft'he high way from'either direction,thejoperation is as ilescribed with respect to "Fig. ,1 although but a single timer and control motor 'is employed.

Consider now the's'ituation where a train occupies section 3, and is, perhaps, engaged in switching operations, and during'this occupancy atrain enters 'section 6, proceeding ina westerly direction. I

I et'us first assume that the'trainenters section 5 after the timing cycle initiated 5 by the occupa'ncy'oi section 3, has 'beencompleted. I In these circumstancearlay 3T is" retracted, relay 48 is stuck up through relay3T down, the clutch mag- 1 net CMI is deenergized andrelay 4T is picked up and thus deenergizes the signals and the motor. The occupancy of section B deprives section 5 of track energy with the result thatinterlocked relay 5T releases and makesup its back points, i

The clutchmagnet CMI is also energized through a to energize the signals and the motor.

circuitincluding contact finger BI and back point, contact finger 62 and back point, contact finger 56 and back point, contact finger 63 and front point, andkcontact -finger 51 and back point. Thus, it is seen that, despite the fact relay ST is released, due to the switching operations taking place, the timerisinitiated as usual because stick relay 4S atthis time is energized. 1 s 7 Accordingly, whether thetrain proceeds across the highway, or whether it engages in switching movements, the operations proceed as if there wereno occupancy of section 3.

requirementsof practice without in any manner departing from the spirit and scope of the invention except insofar as limited by the appended claims. a i i i Having described myinvention, I now claim:

1. In a crossing signalysystem, in combination,

a stretch of track intersecting ahighway, a signal at-the intersection, an approachsection' spaced from the highway, a local section connecting the intersection and the approach section, a track circuit. including a track relayassociated with each section, a front point of thetrack relay of the approach section in the track circuit of the On the other hand, if the trainenters from the east before the operation of the timing period initiated by the occupancy of section 3, the operation is somewhat different. The release of track relay 6T opens the circuit of the clutch magnet CMI to discontinue thetiming and pre vent the subsequent picking upof relay 48. Thus, energy is not restored to section 4 since the shunt around the front contact of relay 3T is not closed so that relayLilT does not pick up. Accordingly, the signals remain, energized and likewise, so does the motor. Thus, the signal continues to be displayed as the west bound train approaches and passes over the highway, all due to the released condition of relay 4T. The

other interlocked relay 5T, although deenergized while the train is occupying one or both of blocks 6 and 5, cannot make up its back point, but is, so to speak, on the latch. These interlocked relays operate in the conventional manner: whereby, upon the first releasing, the second, if deenergized, is latched up against making up its back point and cannot make up its back point until after the first relay has beenreenergized, and

then the second relay has been reenergized.

The operation, as described above, is repeated in similar manner if section 6 be occupied when an east bound train enters section 3.

Thus, in the forms of invention described above, in Fig. 1, a single signal operating means and timing means is effective to care for two types of train movements, one in which the train approaching the highwayproceeds at reasonable vious that other types of signals can be employed local section,an energizing circuit for the signal including a back point of the local section relay, a mechanicalcut-out timingmeans effective a predeterminedtime after occupancy of the approach section to close a shunt across the front point of the approach section relay, mechanical flashing means, movable to alternately openan d close the signal circuit, a motor, means operatively connecting the motor to both the timing means and the flashing means, andan energizing circuit for the motor closed upon of the track sections.

2. In a crossing signal system, in combination,

a stretch of track intersecting a highway, a signal at the intersection, an approach section at each side of, and spaced from, the highway, a

local section connecting the highway and each of the approach sections, a track circuit, including a track relay, for each section, a front point of. the track relay for each of the approachsections in the track circuit of the adjacent local section, energizing circuits for the signal and each including a back point of a local section relay, a single normally inefiective timing means made effective a predetermined time after 00- cupancy of either of the approach sections to close a shunt across the front point of the adjacent approach section relay, mechanical flashing means movable to alternately open and close the signal circuits, a motor, means operatively connecting the motor both to the timing means. and the flashing" means, and energizing circuit means for the motor closed upon occupancy of any of the track sections. I

.3. In a highway crossing signal system, in combination, a stretch of track intersecting a highway, a signal at the intersection, at least one timing section of track spaced from the highway,

a siding leading from the timing section, a control section of track extending between the timing section and the intersection, a combined cutout timer and signal flashing means including, amotor, a cut-out timing member operable by the motor, mechanical signal flashing means operably connected to the motor, control means etas likewise various other means for operating the timing wheel can be used if proved expedient.

The above rather specific .description of two forms of the present invention is given solely by way of example, and is not intended in any man ner whatsoever, in a limiting sense. It is to be understood that various modifications, adaptations, and alterations can be applied to meet the iective immediately, upon occupancy of the timing section, and/or the adjacent portion of the siding, to energize the motor and signal and cause the timer to operate through a timing cycle and cause the signal to flash, and means to deenergize the motor and signal upon completion of the timing cycle and despite any'thenoccupancy of the timing section and/or the adjacent portion of the, siding, a part of said control means being connected to the control section and effective, upon its section being occupied, to energize the motor and signal and cause the signal to flash so long as the control section is occupied.

4. In a highwaycrossing signal system, in combination, a stretch oftrack intersecting a high- Way, a signalat the intersection, a timing secoccupancy of either leading from the timing section, a control :secltion of track extending between the timing ,section and the intersection, a combined (11113101112 timer and signal flashing means including, a motor, aacut-out :timing member operable'by the motor, a normally-inoperative clutch between vthe motor 'andtiming member, mechanical signal flashing means operably connected 'to the motor,

:control means effective immediately, upon 1 connected -.to .the control section and effective,

unonits section beingoccupied, ;to energize the :motor and :signalrand cause the signal to flash asolong as the control section isoccupied.

5. In a crossing signal system; in'combinatio-n, a stretcher track intersecting ,ahighway; .a signal at the intersection; an approachsection at each side of and spaced fromthe highway; a

, iaseee eoo "tion for track spaced from the highway, v1a siding zlocazl section connecting the *highway' and each of the approach sections; a track circuit, in.- tclndingsa .track relay, foneach section, the track relays ifOr the local sections being interlocked so "that one responds only to one ,direction oi train movement and-the other resp nds n y o the opposite direction or train movement a front incint of the track reunion-cachet the app h sections bei included in the track circuit of the adjacent local section; energizing circuits for the ,si naland a in l ding a ack p int Of a loca se tion tr ck -re1 y:;-a':no ;ma11y l en rgized ,stickrelay vior each side of the crossing; :a single normally :dee erei ed timing means; a tenerei fine circuit for each stick relay contro ed y the s e' t ming m ans; a fi st icon of n r in its f a essential iP Iti I of the timing means including respectivelya back point of one approach section relay and a i-rontDOint of the,

other approach section relay; anda second pair of energizing circuits fonsaid portion of the tim, ting means including respectively a back point of ;.an-a1pproach;s ection relay, a :back point of the other app oach section ;relay ,and a front point of the @stick relay associated with I said other approach section relay.

-C. ALEXANDER. 

